Respiratory mask and ducting

ABSTRACT

A suction ducting system for use under a conventional surgical mask comprises a pair of divergent hose sections joined at the back of a wearer&#39;&#39;s neck to a primary suction line. The divergent hose sections extend about the sides of the wearer&#39;&#39;s head adjacent his lower jaw and terminate at the cheeks in flattened substantially triangular ports. The ports lie against the wearer&#39;&#39;s cheeks and each diverges from its suction hose to a narrow, elongated mouth that lies closely adjacent to the wearer&#39;&#39;s cheek and extends from a point just below the side of the nose to a point between the corner of the mouth and the chin. Resilient wire stiffeners extend through the suction hoses to resiliently clamp the ducting system to the wearer&#39;&#39;s head. The primary suction line is held in a vertical loop at the back of the head and is formed of a number of readily disconnectable sections that may be individually attached to the back of the wearer&#39;&#39;s gown. The flattened ports are covered by the mask.

United States Patent [72] lnventor Boyd F. Agnew lll Via Lido Nord, Newport Beach, Calif. 92660 [21] Appl. No. 47,414

[22] Filed June 18, 1970 [45] Patented Dec. 7, 1971 [54] RESPIRATORY MASK AND DUCTING 139, 142.3, 146.3,142.4, 142.5, 140 R, 145 R, 195; 2/2, DIG. 7

[56] References Cited UNITED STATES PATENTS 2,333,054 10/1943 Sullivan 128/142.3 3,529,594 9/1970 Charnley 128/ 1 39 2,688,962 9/1954 Summers ABSTRACT: A suction ducting system for use under a conventional surgical mask comprises a pair of divergent hose sectionsjoined at the back ofa wearer's neck to a primary suction line. The divergent hose sections extend about the sides of the wearer's head adjacent his lower jaw and terminate at the cheeks in flattened substantially triangular ports. The ports lie against the wearer's cheeks and each diverges from its suction hose to a narrow, elongated mouth that lies closely adjacent to the wearer's cheek and extends from a point just below the side of the nose to a point between the corner of the mouth and the chin. Resilient wire stiffeners extend through the suction hoses to resiliently clamp the ducting system to the wearer's head. The primary suction line is held in a vertical loop at the back of the head and is formed of a number of readily disconnectable sections that may be individually attached to the back of the wearer's gown. The flattened ports are covered by the mask.

PATENTEDUEB 7m 3'625'207 sum 1 or 2 ATTORNEYS PATENTEDUEB' Hen 3625207 SHEET 2 BF 2 a n u \NVEMOR BOYD E AGMEW BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of respiratory aids and more particularly concerns a suction ducting system specifically adapted to enhance and facilitate use of a conventional surgical face mask.

2. Description of Prior Art It has long been known that a major source of infectious bacteria, viruses, and other organisms in the atmosphere of an operating room is the exhalation during breathing and talking by the occupants and, in particular, by the surgical team. The conventional cloth or disposable paper surgical mask is widely used in an attempt to minimize dissemination of potentially dangerous organisms. These masks operate by catching and retaining droplets of exhaled moisture which contain bacteria and viruses, to prevent the introduction of these organisms into the atmosphere immediately adjacent the patient and the open surgical wound. However, for operations of long duration of several hours or more, and in particular with patients of lowered resistance, the effectiveness of the conventional masks is initially unsatisfactory, and, moreover, rapidly decreases with time.

Not only is the performance of the conventional mask unsatisfactory, but the mask is difficult to use and becomes increasingly uncomfortable with passage of time. The surgeon must inhale through the mask, thus forcing his lungs to work against the increased restriction of the mask pores. Further, a significant amount of exhaled air of relatively high moisture content and higher temperature is retained at least temporarily within the mask causing still further discomfort.

Cloth masks may not closely fit the wearer's face, particularly around the upper portion of the mask and the bridge of the nose, even though some disposable masks are made with a deformable plastic strip at the upper portion thereof. This strip, after a time, may become displaced or further deformed so as to degrade the fit of the upper portion of the mask. Moist exhaled air that escapes from within the mask upwardly along the upper edges of the mask will cause serious and potentially dangerous fogging of spectacles of the wearer.

In an attempt to solve some of these problems and to avoid contact between the exhaled warm, moist air and the user's glasses, L. Sachs in U.S. Pat. No. 3,288,l38, provides a mask having a pair of smooth conduits at its sides, opening rearwardly to the atmosphere to direct exhaled air away from the surgical working area. This arrangement in no way minimizes the discomfort entailed by the restricted breathing area of the mask, and, in fact, may increase efi'ort required to breathe in and out through the rearwardly directed passages. Furthermore, all of the surgeon's exhalations, together with virusand bacteria-bearing moisture are vented directly into the atmosphere of the operating room. As is well known, such moisture droplets will rapidly evaporate, leaving the potentially dangerous organisms to be diffused throughout the adjoining atmosphere. Such diffusion of airborne particles is achieved in a variety of ways including the mutual repulsion of like electrical charges borne by such particles, air currents generated by temperature variations in different parts of the room, and the deliberate mixing of air in the room by the usual ventilation or air-conditioning system.

Devices shown in U.S. Pats. No. 3,058,463 to E. O. Goodrich, Jr., and U.S. Pat. No. 3,l30,722 to C. A. Dempsey, et al., attempt to overcome these shortcomings by providing a specially constructed face mask, or in the case of the Goodrich device, a mask fully covering the entire head, having a subatmospheric or suction connection to the mask interior. These patents, while apparently effectively venting exhalations of the wearer, both involve specially built complex mask structures, including a helmetlike rigid hood in the case of Goodrich. Each requires a harness to hold the apparatus to the head. They are difficult to put on and take off and become increasingly uncomfortable with prolonged use.

Accordingly, it is an object of the present invention to provide a respiratory apparatus that effectively corrects and disposes of exhalations, is light in weight, comfortable to use, provides maximum freedom of motion, and is readily and simply attached and detached.

SUMMARY OF THE INVENTION Carrying out principles of this invention in accordance with a preferred embodiment thereof, first and second suction hoses diverge from a common junction and thence curve toward each other to terminate in elongated inlet apertures. The inlet apertures are provided by the mouths of substantially flattened ports that are adapted to extend under a conventional disposable surgical mask. The device is maintained in position on the head of the user by means of the resilient clamping action exerted by the hose structure. The common junction of the suction hoses is connected to a main suction line held in a loop at the back of the head of the wearer to provide maximum freedom of head motion. For use with a surgical team, a single suction pump is connected through a manifold to a number of the described suction hoses and ports, one for each member of the team, and the suction provided by the manifold is adjusted in accordance with the number of users at any given time.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I shows the ducting system attached to a wearer, with part of the surgical mask broken away,

FIG. 2 is a side view of the system attached to a wearer, with the mask removed,

FIG. 3 is a side view of the system in use,

FIG. 4 illustrates the suction Y and certain hoses connected thereto, and

F IG. 5 shows a suction source and manifold.

DETAILED DESCRIPTION Referring now to the drawings, and in particular, the illustrations of FIGS. 2 and 4, a ducting system constructed in accordance with the principles of the present invention, comprises a generally Y-shaped arrangement of hoses having a primary leg adapted to be connected to a main suction line and having branch legs that diverge, from a common junction with the primary leg, around the sides of the head of the user to terminate in elongated slots provided by flattened porting devices. The ducting system comprises a rigid Y-connector 12 having a hollow main stem 14 and a pair of interconnected hollow furcations l6 and 18. Connector 112 has a smooth bore and a smooth exterior. Each of the furcations is snugly inserted into a respective one of a pair of flexible and resilient plastic tubes 20 and 22. Each tube terminates in a porting device 24, 26 that has a throat or stem 28, 30, inserted into and frictionally held within the ends of the respective tubes or hoses 20, 22.

Porting devices 24, 26, are formed with integral substantially flattened triangular body portions 32, 34, of which one side may be planar, and the other side formed with a slight concavity to better fit the checks of the wearer. The port bodies terminate in inlet slots or elongated apertures 40, 42, which enable the apparatus to achieve suction over a wide area on each side of the mask as will be described below.

The main stem 14 of the rigid Y-connector 12 is inserted into a first section 44 of a primary suction line including a number of sections 46, 48, 50 and 52. Suction line sections 44 through 52 are preferably formed of a readily flexible bellowstype neoprene hose of which the sections are readily and detachably connected to each other by means of simple friction-type tubular connectors such as the connector illustrated at 54 between primary suction line sections 44 and 46.

A resilient preformed stiffener such as a spring steel wire 56 extends from a blunted end thereof within the throat 28 of the port 24 through the suction hose 20, through the Y-connector furcation 16. At the Y-junction, the stiffener is bent into a sharp V, and extends therefrom through the second furcation 18, through the second suction hose 22 to terminate in a second blunted end portion within the throat 30 of port 26. As illustrated in FIGS. 1-4, stiffener 56 is shaped to hold the suction ducting on the wearer's head without any further harness, straps, or securing devices. The resilience and unstressed configuration of the stiffener 56 presses the ports 24, 26, against the user's cheeks and holds the hoses 20, 22 in the illustrated curved configuration, extending from the back of the neck toward the cheeks of the wearer.

ln assembly of the Y-shaped suction hose system, the spring wire is first inserted into the Y-connector 12 with the wire 56 being doubled and having both of its free ends simultaneously inserted through the end of main stem 14. The respective wire ends then extend through the furcations l6 and 18. The wire 56 is previously formed with the sharp bend of about 30 that mates with the angulation of the two furcations of the connector. After insertion into the connector 12, the wire 56 is bent to the desired configuration that provides the gentle downward, outward, and thence inward curvature desired for the suction hoses 20, 22. Now hoses 20, 22 have the interiors of end portions coated with adhesive. The hoses are slipped over the wire ends and over the furcations l6 and 18.

Ports 24, 26 are performed. Conveniently, these may be made of a thermoplastic funnel that is heated, flattened and then provided with the desired shape. Throats of the ports are then coated with adhesive and these are inserted into the free ends of hoses and 22 with the desired orientation of the length of slots 40 and 42 substantially normal to the horizontal plane of curvature of the hoses 20 and 22.

With the arrangement and configuration of the described Y- shaped hose system, the ends may be readily separated and the device placed over and around the sides of the head of the wearer.

As best seen, in FIGS. 2 and 3, when in use, the main stem 14 of the connector 12 extends upwardly at the back of the head and furcations l6 and 18 extend downwardly toward either side. Hoses 20 and 22 diverge in a gentle curve from the furcations l6 and 18, curving outwardly and forwardly around the back of the neck, to then curve inwardly toward each other. As illustrated in FIG. 4, the stiffener 56 has a free unstressed configuration that holds hoses 20 and 22 in the described shape and positions the respective ports 24 and 26 about I to 2 inches from each other as viewed from above. Due to the stiffener, the hoses 20 and 22 have a compound curvature curving toward each other in a substantially horizontal plane after curving downwardly from the Y-connector in a vertical direction. The flattened diverging ports 24, 26 are oriented so that the elongated inlet apertures 40 and 42 extend at a substantial angle to the horizontal plane of curvature of the hoses 20, 22. That is, the apertures 40 and 42 are normally substantially vertically oriented when in use.

Although the various sections of bellow-type suction line are readily connected and disconnected by means of the slipon friction-type fittings 54, all of the hoses connected to the several branches of Yconnector 12 are permanently secured as by use of a suitable adhesive. Likewise, the throats 28, 30 of ports 24, 26 are permanently secured to the hoses 20, 22.

As illustrated in FIG, 4, the first section 44 of the main suction line which is permanently affixed to the connector 12 is relatively short, preferably on the order of 3 inches. The second section 46 of the main suction line is looped as illustrated in H08. 2 and 3 and may be several feet in length. This section extends to its end portion which is connected to the next longer section of main suction line 48. At a point about 1 foot from its connection with the first suction line section 44, suction line 46 has connected thereto a pair of gown-attaching devices such as conventional alligator clips 60, 62. Subsequent lower sections of the suction hose such as section 48 also are provided with hose-securing devices such as alligator clips 64, 66 for attachment to the gown of the wearer. Note that the alligator clips secure only the suction line to the wearers gown and in no way are used or needed for attachment of any part of the Y-shaped ducting system including hose sections 20, 22 and 44, and ports 24, 26. As previously described, the Y- shaped ducting system, its hoses and ports are held in place solely by the spring action of the stiffener within hoses 20, 22. ln this connection, it may be noted that the entire arrangement is preferably made of a lightweight plastic material, whereby the entire assembly from suction hose section 44 through and including the Y-connector l2, hoses 20,22, ports 24, 26, and the spring wire therein, will weigh about a total of 4 ounces.

The pair of alligator clips 60, 62 which extend from their point of common attachment to suction line section 46, to attachment to the wearer's gown on either side of his upper chest, operates to hold the section 46 in the vertically extending loop illustrated in FIGS. 2 and 3. The looped arrangement allows full freedom of motion of the head of the wearer.

As previously indicated, the spring tension of the hoses and their stiffener is all that is required to hold the suction device in place. The conventional disposable mask 68 is then attached to the face in the usual manner with the sides of the mask extending over and fully covering the flattened diverging ports 24, 26. The elongated apertures of the ports are positioned just behind the comers of the mouth and extend from a point just below the side of the nose to a point substantially midway between the corner of the mouth and the chin. The substantial vertical extent of the apertures 40, 42 achieves a full and complete withdrawal of air from the interior of the mask.

A common surgical team includes a surgeon, an assistant surgeon and two instrument nurses. Also present within the operating room, although not immediately adjacent the patient, are an instrument tray nurse, an anesthesiologist and possibly some observers Accordingly, it is desirable to provide ducting systems for at least four persons, although it will be readily appreciated that ducting systems may be employed for any desired number of people within the room. illustrated in H6. 5 is a suction source and manifold specifically arranged to provide the required negative pressure for a fourman operating room. A housing 70 completely encloses a vacuum pump (not shown) and includes air-intake and air-exhaust ports 72 and 74 at one end thereof. The housing is preferably mounted on casters or the like for ready portability. The negative pressure side of the pump is connected to a U- shaped manifold 78, having four stub-outs 80, 82, 84, 86 for ready attachment to four main suction lines for a conventional operating team Connection between the bellows suction hose and the stub-outs through 86 are conventional friction joints so that the hoses may be attached or detached without use of any special tools. Detachable caps, 76, are provided for each of the stub-outs so that when less than four masks are being supplied by the suction source, the stub-outs not in use may be closed.

An on-off switch 88 is mounted on the housing 70 for control of power to the suction pump and a control knob 90 is carried on the housing and connected to a valve (not shown) in the suction line within the housing. The control knob 90 allows the magnitude of suction to be adjusted to meet requirements of the mask or masks in use. Thus, a constant pressure suction pump is provided and the flow rate produced by the pump is variably controlled by operation of the control knob 90. If all four of the stub-outs are connected to masks in use, a near-maximum suction is provided. lf only one or two of the masks are in use, the control knob 90 is operated to decrease the flow rate.

Regardless of the number of masks actually connected to the manifold 78, the flow rates to the individual masks may be regulated to induct an amount of air through each mask that is slightly greater than the amount of air inspired by the wearer. Normal variations between inspiration rates of different individuals are of such small magnitude that a single adjustment of the dial 90 is effective for regulation of intake or induction rates at all four masks that may be in use.

Adjustment of the suction ensures that the suction source performs all of the work required to induct air from the ambient atmosphere, through the mask to the vicinity of the nose and mouth of the wearer. He is accordingly entirely relieved of this effort, which may be considerable over a period of several hours.

Further, the air that is being breathed is always the cooler air that has been drawn into the mask rather than the mixture of such air and the recently exhaled breath of the wearer.

Since air within the mask is withdrawn, none of this air, whether moist or not will escape upwardly to defog glasses of the wearer. Thus, the disposable mask need not include the usual deformable plastic strip that is bent to conform with the bridge of the nose of the wearer.

The exhalations that are withdrawn from the mask are vented at a distant location through the exhaust aperture of the suction source 70. The latter, of course, may be positioned at any convenient location within the room depending only upon the length of main suction line that is employed. Conveniently, the exhaust aperture of the suction source may be placed closely adjacent an exhaust aperture of the air-conditioning system of the operating room itself, so that substantially all of the air exhausted from the mask and through the suction source 70, is immediately vented to the exhaust system of the room. Also contemplated for use with this invention is the provision of suitable filters or sterilizationdevices within the housing of the suction source 70 to trap or kill or otherwise render impotent the potentially dangerous organisms borne in the usual exhalations.

In some situations, particularly those where combustible or explosive mixtures are employed, extensive precautions are taken to avoid the buildup of static electrical charges. For use in such applications, the main suction line sections may be provided with electrical connections for suitably grounding any static charge that may build up upon plastic parts or hoses or other portions of the apparatus. Conveniently, an electrically conductive wire may be connected to the wire stiffener 56 and extend through the connector 12, through one or more of the main suction lines 44, 46 and 48 to a suitable ground connection. For greater convenience, the electrical conductor may be provided with suitable electrical contact with the connectors such as connector 54. The connectors may be formed with an electrically conductive path whereby the ready attachability and detachability of the hose sections are not impaired and yet, when connected, a continuous ground line is provided.

, The described apparatus is particularly designed for quiet operation. The housing of the suction source 70 is provided with sound insulation to minimize noise from the pump. The design of the various air passages and in particular the large size of the ports further contributes to the substantially noiseless operation.

The optimum convenience of use, attachment and detachment of the apparatus involves a number of different features. Lightweight of the Y-shaped ducting 20, 22, 44, and the self-attaching feature provided by the resilient stiffener makes the device exceedingly easy to put on, to wear for extended periods, and to remove. The loop in main suction line 46 provides complete freedom of head motion and the suction line sections are readily attached to each other and detached from each other, so that the entire apparatus may be quickly connected or disconnected to and from the suction source and to and from the wearer himself.

There has been described an improved ducting system for use with a surgical mask that provides maximized protection against exhaled organisms, is readily attached and detached without any harness connections to the wearer's head, and minimizes impediments to breathing to better enable the surgeon to withstand nervous and physical strain of surgery with less fatigue.

The foregoing detailed description is to be clearly un derstood as given by way of illustration and example only, the spirit and scope of this invention being limited solely by the appended claims.

I claim:

1. Ducting apparatus for use with a respiratory mask comprising a Y-shaped conduit having a primary leg and a pair of branch legs diverging therefrom, and a pair of ports respectively in fluid communication with the ends of said branch legs remote from said primary leg, each said port comprising a substantially flattened, hollow triangular body, said body being secured at an apex thereof to its associated conduit leg, and having an aperture at such apex communicating with the conduit leg, said body diverging outwardly from said apex to form a relatively narrow, elongated mouth, 7 said conduit being proportioned to cause said branch legs to be adapted to extend from their junction with said primary leg at the back of the neck of the wearer forwardly along opposite sides of the neck and head adjacent the lower jaw, with said ports adapted to extend closely adjacent the cheek of the wearer to position the mouths of the ports at opposite comers of the wearer's mouth, said conduit including means for resiliently urging said branch legs toward each other so that the apparatus is adapted to resiliently clamp to the head of the wearer.

2. The apparatus of claim 1 including means adapted to maintain said primary leg in a looped configuration adjacent the back of the head of the wearer, whereby said primary leg may be connected to a main hose that is permitted relatively little motion with respect to the wearer and branch legs may still freely follow motion of the wearers head.-

3. The apparatus of claim 1 including a pressure source, a manifold connected to receive pressure from said source, said manifold having a plurality of wearers hose couplings, a main wearers hose secured to one of said couplings, and valve means on the manifold for controlling flow therethrough in accordance with the number ofwearers' hoses secured to said couplings.

4. The apparatus of claim 1 wherein each of said branch legs is adapted to curve inwardly toward the other, to extend from a point at the back of the neck of the wearer, forwardly around the neck to a point near the back of the lower jaw.

5. Ducting apparatus for use with a respiratory mask comprising a Y-shaped conduit having a primary leg and a pair of branch legs diverging therefrom, and a pair of ports respectively in fluid communication with the ends of said branch legs remote from said primary leg, each said port comprising a substantially flattened, hollow triangular body, said body being secured at an apex thereof to its associated conduit leg, and having an aperture at such apex communicating with the conduit leg, said body diverging outwardly from said apex to form a relatively narrow, elongated mouth, said conduit being proportioned to cause said branch legs to be adapted to extend from their junction with said primary leg at the back of the neck of the wearer forwardly along opposite sides of the neck and head adjacent the lower jaw, with said .ports adapted to extend closely adjacent the cheek of the wearer to position the mouths of the ports at opposite corners of the wearers mouth, and

means for resiliently urging said branch legs toward each other, whereby said ports are adapted to be held in place against the cheeks by clamping action exerted by said branch legs.

6. In combination a flexible porous oronasal surgical mask adapted to be secured to and over the face of the wearer, said mask having means thereon to secure said mask to the head of the wearer, said mask having side portions adapted to lie along the sides of the wearer's face, and ducting therefor, said ducting being separate from said mask and including means adapted to secure the ducting to the wearer independently of the securement of said mask, said ducting comprising a Y- shaped conduit having a primary leg adapted to be joined at the back of the wearer's head to a pair of branch legs adapted to extend forwardly along the sides of the wearers head, each leg terminating in a substantially flat forwardly flaring port, each port extending under one of said side portions and having an elongated mouth extending substantially vertically in a parallel relationship to the adjacent one of said side portions whereby it is adapted to lie at a location below the comer of the wearer's mouth and adjacent the wearers nose.

7. In the combination of a flexible porous surgical mask adapted to be secured to and over the face of a wearer, together with ducting comprising a Y-shaped conduit having a primary leg adapted to be joined at the back of the wearers head to a pair of branch legs adapted to extend forwardly along the sides of the wearers head, each leg terminating in a substantially flat forwardly flaring port, each said port underlying said mask and having an elongated mouth adapted to extend substantially vertically from a point below the corner of the wearer's mouth to a point adjacent the wearers nose, the improvement comprising means for resiliently urging said branch legs toward each other, whereby the ducting is adapted to be secured to the wearers head by pressure of said ports against his cheeks.

8. For use with a surgical mask, a ducting system comprising first and second hoses diverging from a common junction and each having an end portion curving and resiliently urged toward the other, a port secured to each said end portion, each port comprising a hollow substantially flattened body diverging from its connection to an associated hose end portion to form a mouth that is elongated in a direction substantially angulated with respect to the plane of curvature of the end portions, and

a primary hose having one end connected in fluid communication with said first and second hoses at said common junction, and having the other end thereof adapted to be connected with a source of pressure.

9. The system of claim 8 wherein said other end of the primary hose is connected with a negative pressure manifold.

10. For use with a surgical mask, a ducting system comprising first and second hoses diverging from a common junction and each having an end portion curving toward the other, a port secured to each said end portion, each port comprising a hollow substantially flattened body diverging from its connection to an associated hose end portion to form a mouth that is elongated in a direction substantially angulated with respect to the plane of curvature of the end portions, a primary hose having one end connected in fluid communication with said first and second hoses at said common junction, and having the other end thereof adapted to be connected with a source of pressure, and

resilient stiffening means in said first and second hoses for maintaining the shape of said hoses and urging said end portions toward each other, whereby said ducting system is adapted to be attached to a wearer by pressure of said ports against the wearers cheeks.

11. The system ofclaim 10 including attaching means secured to said primary hose at an intermediate point thereof spaced from said common junction, said attaching means including means adapted for connection with the wearer, whereby said intermediate point may be retained at the back of the wearers neck in proximity to said common junction, and whereby said primary hose extends in a loop between said intermediate point and said common junction.

12. Ducting apparatus for use with a respiratory mask comprising a conduit having a primary leg adapted to be positioned behind the head of the wearer and a pair of branch legs connected with said primary leg adapted to extend forwardly along opposite sides of the head of the wearer, each said branch leg terminating in a port adapted to be positioned adjacent the cheeks of the wearer, and

means for resiliently urging said branch legs toward each other, whereby said conduit is adapted to be secured to the head of the wearer by clamping action of said ports against the cheeks of the wearer.

13. The apparatus of claim 12 wherein said means for resiliently urging said branch legs comprises a spring stiffener extending from one of said branch legs to the other.

14. The apparatus of claim 13 wherein said spring stiffener comprises an elongated spring element extending along both said branch legs and at least a portion of said primary leg. 

1. Ducting apparatus for use with a respiratory mask comprising a Y-shaped conduit having a primary leg and a pair of branch legs diverging therefrom, and a pair of ports respectively in fluid communication with the ends of said branch legs remote from said primary leg, each said port comprising a substantially flattened, hollow triangular body, said body being secured at an apex thereof to its associated conduit leg, and having an aperture at such apex communicating with the conduit leg, said body diverging outwardly from said apex to form a relatively narrow, elongated mouth, said conduit being proportioned to cause said branch legs to be adapted to extend from their junction with said primary leg at the back of the neck of the wearer forwardly along opposite sides of the neck and head adjacent the lower jaw, with said ports adapted to extend closely adjacent the cheek of the wearer to position the mouths of the ports at opposite corners of the wearer''s mouth, said conduit including means for resiliently urging said branch legs toward each other so that the apparatus is adapted to resiliently clamp to the head of the wearer.
 2. The apparatus of claim 1 including means adapted to maintain said primary leg in a looped configuration adjacent the back of the head of the wearer, whereby said primary leg may be connected to a main hose that is permitted relatively little motion with respect to the wearer and branch legs may still freely follow motion of the wearer''s head.
 3. The apparatus of claim 1 including a pressure source, a manifold connected to receive pressure from said source, said manifold havinG a plurality of wearer''s hose couplings, a main wearer''s hose secured to one of said couplings, and valve means on the manifold for controlling flow therethrough in accordance with the number of wearers'' hoses secured to said couplings.
 4. The apparatus of claim 1 wherein each of said branch legs is adapted to curve inwardly toward the other, to extend from a point at the back of the neck of the wearer, forwardly around the neck to a point near the back of the lower jaw.
 5. Ducting apparatus for use with a respiratory mask comprising a Y-shaped conduit having a primary leg and a pair of branch legs diverging therefrom, and a pair of ports respectively in fluid communication with the ends of said branch legs remote from said primary leg, each said port comprising a substantially flattened, hollow triangular body, said body being secured at an apex thereof to its associated conduit leg, and having an aperture at such apex communicating with the conduit leg, said body diverging outwardly from said apex to form a relatively narrow, elongated mouth, said conduit being proportioned to cause said branch legs to be adapted to extend from their junction with said primary leg at the back of the neck of the wearer forwardly along opposite sides of the neck and head adjacent the lower jaw, with said ports adapted to extend closely adjacent the cheek of the wearer to position the mouths of the ports at opposite corners of the wearer''s mouth, and means for resiliently urging said branch legs toward each other, whereby said ports are adapted to be held in place against the cheeks by clamping action exerted by said branch legs.
 6. In combination a flexible porous oronasal surgical mask adapted to be secured to and over the face of the wearer, said mask having means thereon to secure said mask to the head of the wearer, said mask having side portions adapted to lie along the sides of the wearer''s face, and ducting therefor, said ducting being separate from said mask and including means adapted to secure the ducting to the wearer independently of the securement of said mask, said ducting comprising a Y-shaped conduit having a primary leg adapted to be joined at the back of the wearer''s head to a pair of branch legs adapted to extend forwardly along the sides of the wearer''s head, each leg terminating in a substantially flat forwardly flaring port, each port extending under one of said side portions and having an elongated mouth extending substantially vertically in a parallel relationship to the adjacent one of said side portions whereby it is adapted to lie at a location below the corner of the wearer''s mouth and adjacent the wearer''s nose.
 7. In the combination of a flexible porous surgical mask adapted to be secured to and over the face of a wearer, together with ducting comprising a Y-shaped conduit having a primary leg adapted to be joined at the back of the wearer''s head to a pair of branch legs adapted to extend forwardly along the sides of the wearer''s head, each leg terminating in a substantially flat forwardly flaring port, each said port underlying said mask and having an elongated mouth adapted to extend substantially vertically from a point below the corner of the wearer''s mouth to a point adjacent the wearer''s nose, the improvement comprising means for resiliently urging said branch legs toward each other, whereby the ducting is adapted to be secured to the wearer''s head by pressure of said ports against his cheeks.
 8. For use with a surgical mask, a ducting system comprising first and second hoses diverging from a common junction and each having an end portion curving and resiliently urged toward the other, a port secured to each said end portion, each port comprising a hollow substantially flattened body diverging from its connection to an associated hose end portion to form a mouth that is elongated in a direction substantially angulated with respect to the plane of curvature of tHe end portions, and a primary hose having one end connected in fluid communication with said first and second hoses at said common junction, and having the other end thereof adapted to be connected with a source of pressure.
 9. The system of claim 8 wherein said other end of the primary hose is connected with a negative pressure manifold.
 10. For use with a surgical mask, a ducting system comprising first and second hoses diverging from a common junction and each having an end portion curving toward the other, a port secured to each said end portion, each port comprising a hollow substantially flattened body diverging from its connection to an associated hose end portion to form a mouth that is elongated in a direction substantially angulated with respect to the plane of curvature of the end portions, a primary hose having one end connected in fluid communication with said first and second hoses at said common junction, and having the other end thereof adapted to be connected with a source of pressure, and resilient stiffening means in said first and second hoses for maintaining the shape of said hoses and urging said end portions toward each other, whereby said ducting system is adapted to be attached to a wearer by pressure of said ports against the wearer''s cheeks.
 11. The system of claim 10 including attaching means secured to said primary hose at an intermediate point thereof spaced from said common junction, said attaching means including means adapted for connection with the wearer, whereby said intermediate point may be retained at the back of the wearer''s neck in proximity to said common junction, and whereby said primary hose extends in a loop between said intermediate point and said common junction.
 12. Ducting apparatus for use with a respiratory mask comprising a conduit having a primary leg adapted to be positioned behind the head of the wearer and a pair of branch legs connected with said primary leg adapted to extend forwardly along opposite sides of the head of the wearer, each said branch leg terminating in a port adapted to be positioned adjacent the cheeks of the wearer, and means for resiliently urging said branch legs toward each other, whereby said conduit is adapted to be secured to the head of the wearer by clamping action of said ports against the cheeks of the wearer.
 13. The apparatus of claim 12 wherein said means for resiliently urging said branch legs comprises a spring stiffener extending from one of said branch legs to the other.
 14. The apparatus of claim 13 wherein said spring stiffener comprises an elongated spring element extending along both said branch legs and at least a portion of said primary leg. 